The obstructive sleep apnea syndrome (OSAS) is an important cause of morbidity in children. Most children present with a history of snoring and difficulty breathing during sleep. However, many children presenting with these symptoms have negative sleep studies, and are diagnosed as having "primary snoring". It is not known whether primary snoring (PS) progresses to the obstructive sleep apnea syndrome. We therefore repeated sleep studies in 6 children with previously-diagnosed PS. All children had negative polysomnograms 1-2 years prior to the present study. Mean age was 8 + 4 (SD) years. Repeat polysomnograms were negative in 5 subjects; one child (17%) demonstrated mild OSAS. We conclude that most patients with PS will not progress to OSAS over the course of 1-2 years. However, more patients need to be studied.